1. Field of Invention
The present invention is related to compositions for removing algae from a variety of surfaces.
2. Description of the Related Art
Especially in hot and humid environments, algae can grow on a variety of surfaces, both interior as well as exterior. The removal of algae from exterior as well as interior surfaces can be a time-consuming and rather unpleasant job, in particular where the surface area to be treated is rather large and/or exceptionally dirty with oil. A common algaecide is sodium hypochlorite. DPC Industries, Inc. of Houston, Tex. markets a useful algaecide composition, "DIXICHLOR", which consists of sodium hypochlorite, sodium chloride, sodium hydroxide, and water. Another algaecide composition, which was invented by the inventor of the present invention and the subject of U.S. Pat. No. 5,856,272 (and is incorporated by reference herein in its entirety) is currently marketed by Magnum Cleaning Products (Galveston, Tex.) as MAGNACHLOR. MAGNACHLOR contains about 10% sodium hypochlorite. To the best of the inventor's knowledge, most if not all algaecide agents on the market comprise sodium hypochlorite, which is believed to be necessary in eradicating algae.
Sodium hypochlorite, while an excellent algaecidal agent, can be hazardous to work with. The compound reacts vigorously with sodium hydroxide, for example, resulting in noxious fumes that are very irritating to the user's eyes, causing blurring and tearing. The compound may also cause skin irritation as well as irritation to sensitive mucousal membranes of the mouth and nose when inhaled.
Most algaecidal agents are formulated and marketed as liquids; however, such liquid formulations have certain undesirable disadvantages, notwithstanding their overall effectiveness in eradicating algae. For example, liquid algaecidal agents comprising sodium hypochlorite have limited shelf lives, generally ranging from six to eight months. Transportation of liquid formulations can also be expensive and hazardous if large quantities of the algaecidal composition are desired (generally, a gallon solution comprises about 10% of sodium hypochlorite). Conversely, a concentrated algaecidal solid formulation can be more easily shipped, and more importantly, has an indefinite shelf-life, since the solid compounds comprising the solid formulation would not be activated until mixed in water or other suitable liquid carrier.
It would therefore be desirable to have an algaecide formulated in a concentrated solid that, just prior to use, can simply be mixed with water or other suitable liquid carrier in a single step. While sodium hypochlorite is available in solid form, it will not work effectively alone if mixed in water and then applied to an algae-covered surface. Moreover, combining sodium hypochlorite and sodium hydroxide in solid form will not effectively kill the algae, since this combination, at the desired algaecidal percentages (about 10% sodium hypochlorite and 1% sodium hydroxide) exceeds the solubility of sodium hypochlorite, thereby resulting in the sodium hypochlorite falling out of solution upon mixing.